<!DOCTYPE html>
<html>
<head>
    <meta charset="utf-8">
    <title>在线尝试 Bootstrap 实例</title>
    <link rel="stylesheet" href="https://cdn.bootcss.com/bootstrap/3.3.7/css/bootstrap.min.css">
    <script src="https://cdn.bootcss.com/jquery/2.1.1/jquery.min.js"></script>
    <script src="https://cdn.bootcss.com/bootstrap/3.3.7/js/bootstrap.min.js"></script>
</head>
<body>

<h1>Hello, world!</h1>

</body>
</html>